Search found 99 matches

by tomtom50
Dec 13 2018 6:29pm
Forum: E-Bike General Discussion
Topic: Where are the hq geared hub motors?
Replies: 20
Views: 640

Re: Where are the hq geared hub motors?

I've been rebuilding 2 MACs for my AWD Fatty . Standard Stator and runner, standard gears (but greased with Aeroshell), and with a beefy clutch (up to 170Nm). It has a side entry motor cable and internal gear & temp sensor. Heavy duty use, so far no problem. Been tinkering with the idea of a 2-spee...
by tomtom50
Dec 13 2018 3:20pm
Forum: E-Bike General Discussion
Topic: Where are the hq geared hub motors?
Replies: 20
Views: 640

Re: Where are the hq geared hub motors?

Because hub motors in general suck due to adding mass in the worst possible place and it's not worth making expensive high end geared hubs. It would be too much of a niche product and by the time you get around making everything decent quality and in low volume it will cost over twice as much. Basi...
by tomtom50
Dec 13 2018 9:32am
Forum: E-Bike General Discussion
Topic: Lightest motor for hill climbing and 135mm dropout with disk brake?
Replies: 19
Views: 857

Re: Lightest motor for hill climbing and 135mm dropout with disk brake?

I'm not familiar with measurements from geared hub motors, but I'm familiar with the range of gearhub efficiencies ranging from low 90% range (Sturmey Archer 3sp and comparable) to below 80% (NuVinci). I assume these efficiencies include chain losses, so it's not all gear losses. At the same time, ...
by tomtom50
Dec 12 2018 9:28pm
Forum: E-Bike General Discussion
Topic: Lightest motor for hill climbing and 135mm dropout with disk brake?
Replies: 19
Views: 857

Re: Lightest motor for hill climbing and 135mm dropout with disk brake?

Remember when you're doing your thermal limit estimates that the reduction gearing also suffers some power loss and heat accumulation. I'm guessing on the order of 10%. I got off track on plastic vs metal (confused with another thread). You are totally right gear loss needs to be added to motor eff...
by tomtom50
Dec 12 2018 9:21pm
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 4077
Views: 277941

Re: New "TSDZ2 Torque Sensor Central Motor"

Ron Paul's Blimp wrote:
Dec 12 2018 1:44am
tomtom50 wrote:
Dec 11 2018 11:29pm
Yeah, I bought one and didn't use it. The machining was defective, the offset was less than claimed, really no better than the stock dished 42T spaced back with 1mm washers.
Ugh that sucks. Thanks for the warning.
Yeah. I was too lazy to return it.
by tomtom50
Dec 12 2018 9:18pm
Forum: E-Bike General Discussion
Topic: Lightest motor for hill climbing and 135mm dropout with disk brake?
Replies: 19
Views: 857

Re: Lightest motor for hill climbing and 135mm dropout with disk brake?

Remember when you're doing your thermal limit estimates that the reduction gearing also suffers some power loss and heat accumulation. I'm guessing on the order of 10%. A common number for a planetary stage is 3%. That doesn't increase for double reductions that are achieved using planet gears that...
by tomtom50
Dec 12 2018 12:32am
Forum: E-Bike General Discussion
Topic: Lightest motor for hill climbing and 135mm dropout with disk brake?
Replies: 19
Views: 857

Re: Lightest motor for hill climbing and 135mm dropout with disk brake?

I went to bikecalculator.com. 300 lb up a steep (10%) grade at 5mphis 330W. Very doable, if you are at an efficient hub rpm you will draw 415W, 85W will go to heat in the hub, and a hub can shed 85W. 5mph on a 20 inch wheel is 84rpm, that is where it gets hard. To still be in an efficient motor rang...
by tomtom50
Dec 11 2018 11:48pm
Forum: E-Bike General Discussion
Topic: Where are the hq geared hub motors?
Replies: 20
Views: 640

Re: Where are the hq geared hub motors?

Are the gears a problem? I've seen photos where they failed in over-heated hubs, but how important is it to make gears that are fine but the magnets are ruined? Metal gears could handle more torque, but more torque means more heat, and the heat path in geared hubs is worse than DD hubs. The Aikema Q...
by tomtom50
Dec 11 2018 11:29pm
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 4077
Views: 277941

Re: New "TSDZ2 Torque Sensor Central Motor"

Has anyone used https://www.electrifybike.com/store/p65/42_Tooth_Narrow%2FWide_CNC_7075_T6_Chainring_%2810mm_offset%29_for_TSDZ2.html ? Looking at my motor and the pictures I wonder if it'd interfere where the cables come out of the controller. Yeah, I bought one and didn't use it. The machining wa...
by tomtom50
Dec 09 2018 9:54pm
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 4077
Views: 277941

How to make Waterproof Open Source Firmware Cable

Here is a cable that: Plugs into a standard TSDZ2 motor Doesn't modify the stock setup, so the upgrade can be undone Uses waterproof connectors Plugs directly to the green 5-pin KT-LCD3 cable Works with 8-wire (throttle) TSDZ2 You need two cables: Higo B8 This plugs into the TSDZ2 I bought from http...
by tomtom50
Dec 09 2018 4:36pm
Forum: E-Bike General Discussion
Topic: Best Sub 4KG hub motor ?
Replies: 29
Views: 1181

Re: Best Sub 4KG hub motor ?

Title sums it up: what's the most powerfull hub motor under 4KG currently available - APART FROM THE XIONGDA 2 SPEED ? That one does not fit into my aluminium (disc only) frame. I'm surprised no one mentioned the Aikema 128 in this thread. 2.8kg Two basic versions, 500W and 800W "H" Sold by BMS bat...
by tomtom50
Dec 09 2018 2:33pm
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 4077
Views: 277941

Re: New "TSDZ2 Torque Sensor Central Motor"

[quote=tomtom50 post_id=1430428 time=1544321617 Are you guys building your own packs? GA cell 13S2P is hard to find. I almost had one custom built, but I already have a (heavy) 14S3P pack I can use on both bikes so it was hard to justify. I do..I love the flexibility and you can save alot of money....
by tomtom50
Dec 08 2018 9:13pm
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 4077
Views: 277941

Re: New "TSDZ2 Torque Sensor Central Motor"

Exactly Andy.. I like 14s but 14s2p is not enough and 14s3p would be way too heavy unless there are some better cells out there than the GA's ? 15s2p is tempting but will it blow the display ? And can you get a 15s bms to suit ? It really depends if you want a heavy commuter or playful jump bike.. ...
by tomtom50
Dec 07 2018 12:18am
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 4077
Views: 277941

Re: New "TSDZ2 Torque Sensor Central Motor"

endlesscadence has asked me to write down some kind of "how to go about it". He meant to go over it and post it on the wiki, but i am afraid he is no longer active. at least i have not see him post here for 2 weeks or so. So therefore i am attaching what i have so far, there may be some mistakes in...
by tomtom50
Dec 05 2018 9:14pm
Forum: E-Bike Technical
Topic: Wattage vs Torque/Pulling Power.
Replies: 25
Views: 2461

Re: Wattage vs Torque/Pulling Power.

Or use the Grin Cycles simulator tool which can work out all this stuff for you ;) The Grin simulator has some drawbacks: 1. The Grin simulator graphs are not standard. Motor performance sheets graph motor data against torque. They start a motor at no-load and apply increasing torque. Here is an Ai...
by tomtom50
Dec 05 2018 8:54pm
Forum: E-Bike Technical
Topic: Wattage vs Torque/Pulling Power.
Replies: 25
Views: 2461

Re: Wattage vs Torque/Pulling Power.

So just to run an example against the desired speeds and grades, of the power required, even if friction and rolling resistance is zero: power = force x velocity In this case the force is gravity and the velocity is the vertical speed (opposite the force). If we consider 10% a steep grade, then for...
by tomtom50
Dec 03 2018 11:28pm
Forum: E-Bike Technical
Topic: Wattage vs Torque/Pulling Power.
Replies: 25
Views: 2461

Re: Wattage vs Torque/Pulling Power.

Want you are looking for is in one equation: Power = Force X Velocity. Power is watts. You need force to pull up a hill. If Velocity (speed) drops you can still climb that hill at low power. But you might climb slowly. Just like using lowest gear on your mountain bike. This is physics, there is no g...
by tomtom50
Nov 27 2018 9:52pm
Forum: Motor Technology
Topic: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)
Replies: 3330
Views: 142711

Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

I bought this same controller from topbikekit. Have you used it yet? Any results? Did not touch the waterproof fill. Therefore, I use it in stock. Bike and I are about 100kg. Motor bafang BPM 10t 26 ". 48V. It starts moving away if the gas is lightly pressed, otherwise the current exceeds and switc...
by tomtom50
Nov 27 2018 2:23am
Forum: E-Bike Technical
Topic: Bafang G310 geared hub - 11:1 reduction ratio!!!
Replies: 98
Views: 9119

Re: Bafang G310 geared hub - 11:1 reduction ratio!!!

Adjusting wheel sizes to scale the motors to the same no load speeds Ah no, you can't do that for a fair comparison because you are then comparing the motors at different rpms and torques. The smaller wheel size almost always has the advantage since it needs to produce less torque for the same thru...
by tomtom50
Nov 26 2018 11:12pm
Forum: Motor Technology
Topic: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)
Replies: 3330
Views: 142711

Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Hi I got KT48SVPRM-XFCF06 (board KTE-9S5-J5). It has 9 transistors K150E09NE. Processor STM8S105C6T6. Current sensor acs711 (QFN). Is it compatible with this OpenSource firmware? kt48svprm.jpg What are the extra 3 transistors doing? I bought this same controller from topbikekit. Have you used it ye...
by tomtom50
Nov 26 2018 3:10pm
Forum: E-Bike General Discussion
Topic: Q128H Light & Torquey 800W Hub Motor
Replies: 21
Views: 724

Re: Q128H Light & Torquey 800W Hub Motor

Good data right there. If you think about it, the G310 puts out roughly the same power than the Q128H, and is perhaps a hair larger, but it can only expend 132w continuously, and the Q128H is putting out >150W of heat at it's rated 800W. But this hill requires 1100-1200w to maintain any decent spee...
by tomtom50
Nov 26 2018 2:57pm
Forum: E-Bike General Discussion
Topic: Q128H Light & Torquey 800W Hub Motor
Replies: 21
Views: 724

Re: Q128H Light & Torquey 800W Hub Motor

I think there is a 72 volt sine wave controller available but have not tried it. Thanks, that doesn't sound too bad. I read somewhere that the 72V KT controller is set up for 'normal' 24/36/48/60/72 voltages, and that if you connect a 52V pack it decides between 48V and 60V and sets voltage limits ...
by tomtom50
Nov 25 2018 10:33pm
Forum: E-Bike General Discussion
Topic: Q128H Light & Torquey 800W Hub Motor
Replies: 21
Views: 724

Re: Q128H Light & Torquey 800W Hub Motor

I have a Surly Big Dummy cargo bike with Q128h 201 rpm motors front and rear. They are 48 volt motors run at 52 volts. It aint fast, tops out at ~19 mph but it can really climb hills. With both motors pulling it rarely gets below 13 mph on the steepest hills and pulls a fully loaded gross weight of...
by tomtom50
Nov 25 2018 10:27pm
Forum: E-Bike General Discussion
Topic: Q128H Light & Torquey 800W Hub Motor
Replies: 21
Views: 724

Re: Q128H Light & Torquey 800W Hub Motor

Neptronix mentioned the Bafang G210 as another hub motor with similar power and weight. Unfortunately it is only available with windings too fast for climbing an 8% grade with a 700C wheel. (300rpm 36V / 400rpm 48V). They are really similar in construction and size G310Opened.jpg Q128C-135 & G31...
by tomtom50
Nov 25 2018 4:45pm
Forum: E-Bike General Discussion
Topic: Q128H Light & Torquey 800W Hub Motor
Replies: 21
Views: 724

Servicing & Gear Reduction (48V 201rpm Q128H)

Nice CAD view CAD View.png The CAD view is current, everthing I saw inside matches. 1. To open unscrew the cover (freewheel side) from the hub body and lift out. I held the cover in a vise with aluminum jaw plates and turned the hub with a strap wrench. The hub cover with the free wheel threads is r...